Minerals, Rocks and Minerals, Rocks and FossilsFossils

What is a mineral?What is a mineral?

•Naturally occurringNaturally occurring

•Non-organicNon-organic

•Characteristic chemical Characteristic chemical compositioncomposition

•Distinctive physical propertiesDistinctive physical properties

•Crystalline structureCrystalline structure

Mineral propertiesMineral properties•ColorColor

•LusterLuster

•Habit (Shape)Habit (Shape)

•Cleavage & FractureCleavage & Fracture

•StreakStreak

•HardnessHardness

•OtherOther

Color:Color: Not mineral Not mineral specificspecific

Luster:Luster:How minerals reflect lightHow minerals reflect light

Non-metallic

Metallic

Mineral Habit Mineral Habit (Shape)(Shape)

Shape a Shape a mineral takes mineral takes if grown if grown unimpededunimpeded

Mineral Java AppletMineral Java Applet

Cleavage & FractureCleavage & Fracture

Cleavage: planes of Cleavage: planes of weakness along which weakness along which minerals can breakminerals can break

Fracture: surfaces along Fracture: surfaces along which minerals can breakwhich minerals can break

Cleavage & FractureCleavage & Fracture

Best identified on a fracture surface

Streak:Streak:

The powdered form of a mineralThe powdered form of a mineral

Hardness:Hardness:Based on Moh’s scale of hardnessBased on Moh’s scale of hardness

Other PropertiesOther Properties

•Specific gravitySpecific gravity

•Reaction to acidReaction to acid

•StriationsStriations

•MagnetismMagnetism

Classifying RocksClassifying Rocks

• Rocks are classified by how they formed Rocks are classified by how they formed and what they’re made ofand what they’re made of

• There are 3 general classes of rocksThere are 3 general classes of rocks

• Igneous RocksIgneous Rocks…are formed when lava …are formed when lava and magma crystallize to form solid rockand magma crystallize to form solid rock

• Metamorphic RocksMetamorphic Rocks…are formed when …are formed when an existing rock is partially melted, an existing rock is partially melted, squeezed, or bothsqueezed, or both

• Sedimentary RocksSedimentary Rocks…are formed when …are formed when sediments (sand clay, and silt) are sediments (sand clay, and silt) are compressed and become solid rockcompressed and become solid rock

Igneous Rocks

Metamorphic RocksMetamorphic Rocks

GneissSchist

Sedimentary RocksSedimentary Rocks

Shale

Conglomerate

Sandstone

FossilsFossilsThe remains or imprints of living things of the

past found in Sedimentary rocks.

Fossils provide information about life and Fossils provide information about life and conditions in the past.conditions in the past.

Fossils of Sea CreaturesFossils of Sea Creatures

• Oceans once Oceans once covered the covered the areaarea

• What part of What part of the oceanthe ocean

Fossils of PlantsFossils of Plants

• Plant fossils Plant fossils can tell us can tell us about the about the ancient ancient environmentenvironment

Animal FossilsAnimal Fossils

• Animal fossils can Animal fossils can tell us tell us – About past About past

environmentsenvironments– What the animal What the animal

ateate– How they livedHow they lived